Question 1173432: student was asked to form two-digit numbers using the following digits: 0,1,2,3,4,5,6,7,
and 8.
How many of these are even numbers?
Repeating of digits are not allowed
Can you help me with this?.... thank you so much
Found 2 solutions by ewatrrr, ikleyn:
Answer by ewatrrr(24785)   (Show Source):
You can put this solution on YOUR website!
Hi
form two-digit numbers using the following
9 numbers: 0,1,2,3,4,5,6,7,8
How many ways can Two-digit even numbers be formed:
tens digit 8 choices (not zero)
ones digit 5 choices (0, 2,4,6,8)
8x5 = 40 choices for even numbers
Repeating of digits are not allowed (22,44,66,88)
40 - 4 = 36 is the number of even with no repeating digits
Wish You the Best in your Studies.
Answer by ikleyn(52781)  (Show Source):
You can put this solution on YOUR website! .
First digit can be any of the 8 given digits from 1 to 8 inclusive.
(notice that 0 (zero) can not be the first digit of a two-digit number).
Second digit can be any of the 5 given EVEN digits 0, 2, 4, 6, and 8.
It gives us 8*5 = 40 potential candidates for two digit numbers.
From this amount, we should exclude two-digit numbers with repeating digits.
They are 22, 44, 66, and 88 - in all, 4 numbers must be excluded from 40.
It gives the ANSWER 40 - 4 = 36.
ANSWER. There are 36 two-digit numbers satisfying to imposed conditions.
Solved.
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